X-Ray photograph unit

Abstract

In an X-ray photograph unit of the type which controls an X-ray projection on the basis of a tube voltage, a tube current and an exposure time, this invention relates to an X-ray photograph unit including photograph portion switches disposed so as to correspond to portions of the human body to be photographed and which set primarily and automatically the tube voltage and the tube current, and thickness switches disposed so as to correspond to the thickness of the portions to be photographed and setting automatically the exposure time in combination with said photograph portion switches, wherein the selection of said photograph portion switches and said thickness switches along makes it possible to carry out the X-ray projection.

What is claimed is: 
     
       1. An X-ray photograph unit of the type which controls the X-ray projection on the basis of tube voltage, tube current and exposure time which comprises: an X-ray tube,   a plurality of photography portion switches structured so as to automatically set said tube voltage and tube current to predetermined values corresponding to selected portions of the human body to be photographed,   a plurality of thickness switches structured so as to set automatically the exposure time to correspond to the thickness of human body portions to be photographed in combination with said photograph portion switches,   each of said photograph portion switches being connected in series with a plurality of said thickness switches and each thickness switch in turn being connected in series to first and second timers,   said first timers providing an exposure time pre-determined in accordance with the human body portion to be photographed and with the thickness thereof,   said second timers being protective timers to provide the upper limit of exposure time for each body portion to be photographed equivalent to an exposure time determined in accordance with the maximal thickness for each body portion to be photographed under control of said photograph portion switch,   said photograph portion switches and said thickness switches being electrically connected to said X-ray tube so the selection of one of each said switches alone makes it possible to carry out an X-ray photography projection.   
     
     
       2. The X-ray photograph unit as defined in claim 1 wherein said first timers comprise said photograph portion switches connected in parallel to a d.c. power supply, said thickness switches connected in parallel to each of said photograph portion switches and a timer set value circuit connected to each of said thickness switches. 
     
     
       3. The X-ray photograph unit as defined in claim 1 wherein said second timers comprise said photograph portion switches connected in parallel to a d.c. power supply and a protective timer set value circuit connected to each of said photograph portion switches. 
     
     
       4. The X-ray photograph unit as defined in claim 1 wherein said photograph portion switches are connected in series to respective auxiliary relays so that when each of said photograph portion switches is turned ON, said auxiliary relay corresponding to said photograph portion switch is energized. 
     
     
       5. The X-ray photograph unit as defined in claim 1 wherein said application of voltage to said X-ray tube is through a high-voltage transformer that is energized by operation of one of said auxiliary relays. 
     
     
       6. The X-ray photograph unit of claim 3 wherein said X-ray tube is connected to said high-voltage transformer via a rectification circuit.